What is clear air turbulence?

More than two-dozen passenger were injured after an Aeroflot flight encountered severe turbulence Monday on its way from Moscow to Bangkok.

Video from the incident showed a chaotic scene, including blood on an overhead storage bin and passengers lying prone in aisles.

Aeroflot confirmed the incident of "clear air turbulence," saying "none of the 27 passengers ... has serious or life-threatening injuries." Fifteen Russians and two Thai citizens remained hospitalized Monday, according to the statement. "The patients that are still under doctors’ care have contusions, and several have fractured or broken bones," Aeroflot added.

"Some injured passengers were not wearing seat belts. All victims were taken to a local hospital with various injuries, mostly fractures and bruises. Some require surgery. Fifteen people remain hospitalized," the embassy said, per a report from CNN.

The incident occurred on a Boeing 777-300 operating as Aeroflot Flight 270 with 313 people on board, according to The Aviation Herald, a website that tracks airline safety incidents.

CNN showed video from the aftermath that included images of blood streaked across surfaces and food and personal belongings strewn across the cabin. Some passengers were seen lying in the aisles, presumably having suffered injuries during the turbulence.

One passenger on the flight described the scene to CNN, saying passengers flew out of their seats during the episode.

"It lasted for about ten seconds, the plane was being thrown everywhere," New Jersey resident Rostik Rusev said to the network. "There was blood on the ceiling, people with broken noses, babies who were hurt, it was horrible. It came out of nowhere it was like driving a car and a tire suddenly bursts.”

Still, Rusev lauded the Aeroflot crew for their handling of the situation. He called the crew “heroes,” adding to CNN that they “couldn't have been more professional and courageous.”